The present invention relates to a preparation(composition) which can inhibit propagation of a protista, for instance, in a waterway such as a drain in a refrigerator, a freezer etc. by releasing gradually anti-protista substance contained therein.
The main reason for giving bad influence by a protista such as bacteria, fungi and algae upon living environments is generally existence of water, and water in this sense has included waste water of human life and waste water from factories whose BOD value is high (which are classified into the first group), and rain water, condensation water of vapor formed by change of temperature, circulating water by heat exchangers, circulating water by fixed temperature circulating type bath tubs, condensation water generated from heat exchangers and condensation water generated from air compressors (which are classified into the second group), and so on.
Among them, in those which are classified into the first group, nutrients for bacteria, fungi and algae are originally contained, and in those which are classified into the second group, any means against bacteria, fungi and algae (e.g. using chlorine effective to city water) is originally not adopted.
And, in the first group water, bacteria, fungi and algae propagate themselves, and also in the second group water, they propagate themselves when certain conditions (such as temperature, free contact with outdoor atmosphere and continuous supply of nutrients) are fulfilled, so that there is caused such a problem as generation of bad smell, coloring, pollution and narrowing or blocking drain channels.
For the purpose of solving such problem as above, there have generally been adopted such technologies as a physical removal means comprising scraping off mechanically accumulated protista and/or its metabolites and a chemical treatment comprising adding or spraying periodically antibacterial agents, antifungi agents, antialgae agents, etc. However, those technologies usually require large amount of time and manpower, and further in the chemical treatment, use of very strong inorganic acids, inorganic alkaline substances, oxidizing agents, reducing agents, etc. are generally necessary and therefore environmental pollution and damage to health of workers by the chemicals themselves have generally been feared. Additionally, a long-lasting effect cannot be expected by those technologies and thus these treatments are necessarily required frequently.